The WWW stands for World Wide Web, is a set of protocols that allows you to access any document on the Net through a naming system based on URLs.
WWW also specifies a way, the HTTP, to request and send a document over the Internet. With these standard protocols of WWW in place, one can set up a server and construct hypertext documents with links in them that point to the documents on the server.
Before WWW, Internet was mainly used for obtaining the textual information. But post-WWW, the Internet popularity grew tremendous because of graphic-intensive nature of WWW. Therefore, we may attribute the explosion in use and popularity of Internet to WWW only.